Delphi is survey technique that involves repeated polling of the same individuals, feeding back anonymised responses from earlier rounds of polling, with the idea that this will allow for better judgements to be made without undue influence from forceful or high-status advocates.
How to do it?
Selection of the topic: The subject should be one where there is a lack of hard data on future trends. In some cases, one thematic field is enough, in many cases the aim is to get an overview so that more fields are decided on and handled in a flexible way. There is always the possibility to add, remove or re-name fields.
Designing the questionnaire: Writing the questions or statements. The questions should be clearly defined, possible to answer, and match the statements made. The statements have to be formulated in a way that the criteria or questions can be judged on the basis of them. Other questions may be related to the possible constraints (economical, technological, social, political) to the occurrence of event or development. When designing the questionnaire, it is important to consider from the beginning how to give feedback to the participants during the second round. The usual way is to provide percentages or graphics from the accumulated data in a similar way as in the first round questionnaire. However, there is much room for creativity, especially with online questionnaires.
Selection of the panel of experts: Care is needed in recruiting the panel and the criteria for selection should be set out. Before an expert agrees to take part in a Delphi inquiry, he/she should understand the purpose of the inquiry and should be aware that his/ her expertise should be made available in different rounds of the inquiry. The Delphi method has an iterative nature. If the exercise is to maintain its credibility the tendency for panel members to drop out after the first round should be minimised.
When to use it?
Usually, the goal (and the result) of a Delphi study is to organise a debate, to collect and synthesise opinions and to achieve a degree of convergence. It is a valuable tool for communication and for exchanging opinions on a topic, making experts’ tacit knowledge of the future more explicit. It is also useful for longer-term assessments where extrapolations make no sense. It can help to gather the opinions of a larger group of experts and in fields where there is not a lot of evidence about the developments and where experts often do not dare to explain their real opinion. It is conducted anonymously in order not to let anyone lose face in the event of a change of opinion. The methodology is designed to avoid domination by particular individuals.